This TV remote control receiver uses a ratchet system to activate an old drum-type selector to change channels. A common system at the time. The circuit is from a Radio Electronics from February 1961.
This circuit is from 1995 documentation. Integrated circuits are used which can still be found...
This circuit was found in an old documentation, being able to generate signals of frequencies in...
This 9 V amplifier has a gain of 20 and provides a power of a few hundred milliwatts. The circuit is...